ISTANBUL — The suicide bomber who attacked a wedding party in Gaziantep, near the border with Syria, was between the ages of 12 and 14, Turkish President Recep Tayyip Erdogan said Sunday.

The bombing at the outdoor celebration Saturday in the southeastern Turkish city killed 51 people, Erdogan said. The pro-Kurdish Peoples’ Democratic Party said it was the wedding of one of its members.

At least 69 of those wounded were being treated in the hospital, and 17 were in critical condition, Erdogan said.

The bride and groom – Besna and Nurettin Akdogan – survived the attack and were in the hospital, but were not critically wounded, state-run Anadolu news agency reported.

Prosecutors told the Dogan news agency that the remains of an explosive vest had been found.

“We couldn’t see anything. Nothing but body parts,” Sukru Akdogan, the groom’s brother, was quoted by Anadolu as saying.

Gaziantep, a city of 1.5 million people, is about 25 miles from the Syrian border.

Erdogan blamed the Islamic State for the attack.

“Daesh is trying to position and organize itself in Gaziantep,” he said, using an Arabic acronym for Islamic State.

Images from the scene showed at least one structure on fire, bodies covered in blankets, and blood on the street and walls. Videos posted on social media also showed the chaos, with people using the light on their mobile phones to find victims.

Gulser Ates, who was wounded in the attack, told Anadolu: “I don’t know what happened. The only thing I know is that my neighbor died on top of me.

“If she had not fallen on me, I would have died, too. Her body saved me. … There were innocent children there. No one had done anything wrong.”